[PATCH 2/3] iommu/amd: Don't call early_amd_iommu_init() when AMD IOMMU is disabled

From: Joerg Roedel
Date: Wed Mar 17 2021 - 05:11:52 EST


From: Joerg Roedel <jroedel@xxxxxxx>

Don't even try to initialize the AMD IOMMU hardware when amd_iommu=off has been
passed on the kernel command line.

References: https://bugzilla.kernel.org/show_bug.cgi?id=212133
References: https://bugzilla.suse.com/show_bug.cgi?id=1183132
Cc: stable@xxxxxxxxxxxxxxx # v5.11
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
drivers/iommu/amd/init.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 3280e6f5b720..61dae1800b7f 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -2919,12 +2919,12 @@ static int __init state_next(void)
}
break;
case IOMMU_IVRS_DETECTED:
- ret = early_amd_iommu_init();
- init_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;
- if (init_state == IOMMU_ACPI_FINISHED && amd_iommu_disabled) {
- pr_info("AMD IOMMU disabled\n");
+ if (amd_iommu_disabled) {
init_state = IOMMU_CMDLINE_DISABLED;
ret = -EINVAL;
+ } else {
+ ret = early_amd_iommu_init();
+ init_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;
}
break;
case IOMMU_ACPI_FINISHED:
--
2.30.2